package com.cygnus.util;

import java.util.Random;

public class Utils {
//    给我一个字符串，返回其中任几个字符
    public static String getRandomString(String str){
        Random random=new Random();
        StringBuffer sb=new StringBuffer();
        for(int i=0;i<1;i++){
            int number=random.nextInt(2);
            System.out.println(number);
            sb.append(str.charAt(number));
        }
        return sb.toString();
    }
}
